Intrauterine administration of autologous peripheral blood mononuclear cells promotes implantation rates in patients with repeated failure of IVF–embryo transfer

Role of immune cells in the establishment of implantation and maintenance of pregnancy and immunomodulatory therapies for patients with repeated implantation failure and recurrent pregnancy loss

Background

Immune cells play an important role in the establishment of pregnancy, and abnormalities in the immune system can cause implantation failure and miscarriage.

Methods

Previous papers have been summarized and the role of immune cells in reproduction is reviewed.

Results

The immune environment in the uterus changes drastically from before implantation to after pregnancy to maintain pregnancy. In allogeneic pregnancies, immature dendritic cells (DCs) that induce immune tolerance from outside the uterus flow into the uterus, and mature DCs that remain in the uterus express programmed cell death ligand 2, which suppresses the immune response. Macrophages are classified into M1-macrophages, which induce inflammation, and M2-macrophages, which suppress inflammation; M1-macrophages are required for luteinization, and M2-macrophages induce the differentiation of endometrial epithelial cells to enable implantation. Regulatory T cells, which suppress rejection, are essential for the implantation and maintenance of allogeneic pregnancies. Implantation failure and fetal loss are associated with decreased numbers or qualitative abnormalities of DCs, macrophages, and regulatory T cells. The clinical usefulness of immunomodulatory therapies in patients with repeated implantation failure and recurrent pregnancy loss has been reported.

Conclusion

The provision of individualized medical care in cases of implantation failure or miscarriage may improve clinical outcomes.

The role of Th17 and Treg cells in normal pregnancy and unexplained recurrent spontaneous abortion (URSA): New insights into immune mechanisms

Recurrent spontaneous abortion (RSA) has various causes, including chromosomal abnormalities, a prethrombotic state, and abnormal uterine anatomical factors. However, in about 50% of cases, the cause remains unknown and is referred to as unexplained recurrent spontaneous abortion (URSA). The fetus is protected from rejection by the maternal system, acting as an allogeneic gene, and immune tolerance serves as a crucial mechanism. The Th17/Treg cell paradigm's emergence as a new subpopulation of CD4+ T cells, interacting with one another, plays an essential role in the immune microenvironment and the body's defense system. This Th17/Treg cell model helps to explain the pathology of recurrent miscarriage that could not be accounted for by the original immune mechanism based on the Th1/Th2 model. Furthermore, the plasticity of Th17 and Treg cells holds innovative significance in autoimmunity and abortion. This paper reviews the role of Th17/Treg cellular immune response in the maintaining normal pregnancy and understanding unexplained recurrent spontaneous abortion.

Immunomodulation for unexplained recurrent implantation failure: where are we now?

In brief

Immune dysfunction may contribute to or cause recurrent implantation failure. This article summarizes normal and pathologic immune responses at implantation and critically appraises currently used immunomodulatory therapies.

Abstract

Recurrent implantation failure (RIF) may be defined as the absence of pregnancy despite the transfer of ≥3 good-quality blastocysts and is unexplained in up to 50% of cases. There are currently no effective treatments for patients with unexplained RIF. Since the maternal immune system is intricately involved in mediating endometrial receptivity and embryo implantation, both insufficient and excessive endometrial inflammatory responses during the window of implantation are proposed to lead to implantation failure. Recent strategies to improve conception rates in RIF patients have focused on modulating maternal immune responses at implantation, through either promoting or suppressing inflammation. Unfortunately, there are no validated, readily available diagnostic tests to confirm immune-mediated RIF. As such, immune therapies are often started empirically without robust evidence as to their efficacy. Like other chronic diseases, patient selection for immunomodulatory therapy is crucial, and personalized medicine for RIF patients is emerging. As the literature on the subject is heterogenous and rapidly evolving, we aim to summarize the potential efficacy, mechanisms of actions and side effects of select therapies for the practicing clinician.

Recurrent implantation failure: A comprehensive summary from etiology to treatment

Implantation is the first step in human reproduction. Successful implantation depends on the crosstalk between embryo and endometrium. Recurrent implantation failure (RIF) is a clinical phenomenon characterized by a lack of implantation after the transfer of several embryos and disturbs approximately 10% couples undergoing in vitro fertilization and embryo transfer. Despite increasing literature on RIF, there is still no widely accepted definition or standard protocol for the diagnosis and treatment of RIF. Progress in predicting and preventing RIF has been hampered by a lack of widely accepted definitions. Most couples with RIF can become pregnant after clinical intervention. The prognosis for couples with RIF is related to maternal age. RIF can be caused by immunology, thrombophilias, endometrial receptivity, microbiome, anatomical abnormalities, male factors, and embryo aneuploidy. It is important to determine the most possible etiologies, and individualized treatment aimed at the primary cause seems to be an effective method for increasing the implantation rate. Couples with RIF require psychological support and appropriate clinical intervention. Further studies are required to evaluate diagnostic method and he effectiveness of each therapy, and guide clinical treatment.

Effects of human chorionic gonadotropin-producing peripheral blood mononuclear cells on the endometrial receptivity and implantation sites of the mouse uterus

OBJECTIVE

This research investigated the effects of human chorionic gonadotropin (HCG)-producing peripheral blood mononuclear cells (PBMCs) on the implantation rate and embryo attachment in mice.

METHODS

In this experimental study, a DNA fragment of the HCG gene was cloned into an expression vector, which was transfected into PBMCs. The concentration of the produced HCG was measured using enzyme-linked immunosorbent assay. Embryo attachment was investigated on the co-cultured endometrial cells and PBMCs in vitro. As an in vivo experiment, intrauterine administration of PBMCs was done in plaque-positive female mice. Studied mice were distributed into five groups: control, embryo implantation dysfunction (EID), EID with produced HCG, EID with PBMCs, and EID with HCG-producing PBMCs. Uterine horns were excised to characterize the number of implantation sites and pregnancy rate on day 7.5 post-coitum. During an implantation window, the mRNA expression of genes was evaluated using real-time polymerase chain reaction.

RESULTS

DNA fragments were cloned between the BamHI and EcoRI sites in the vector. About 465 pg/mL of HCG was produced in the transfected PBMCs. The attachment rate, pregnancy rate, and the number of implantation sites were substantially higher in the HCG-producing PBMCs group than in the other groups. Significantly elevated expression of the target genes was observed in the EID with HCG-producing PBMCs group.

CONCLUSION

Alterations in gene expression following the intrauterine injection of HCG-producing PBMCs, could be considered a possible cause of increased embryo attachment rate, pregnancy rate, and the number of implantation sites.

Endometrium Immunomodulation to Prevent Recurrent Implantation Failure in Assisted Reproductive Technology

After more than four decades of assisted reproductive technology (ART) practice worldwide, today more than 60% of women undergoing in vitro fertilization (IVF) treatments fail to become pregnant after the first embryo transfer and nearly 20% of patients are suffering from unexplained recurrent implantation failures (RIFs) and repeated pregnancy loss (RPL). The literature reported different causes of RIF–RPL, mainly multifactorial, endometrial and idiopathic. RIF remains a black box because of the complicated categorization and causes of this physio-pathological dysregulation of implantation and pregnancy process after ovarian stimulation. Many options were suggested as solutions to treat RIF–RPL with controversial results on their usefulness. In this article, we reviewed different possible therapeutic options to improve implantation rates and clinical outcomes. Based on our experience we believe that endometrium immunomodulation after intrauterine insemination of activated autologous peripheral blood mononuclear cells (PBMCs) or platelet-rich plasma (PRP) can be a promising therapeutic solution. On the other hand, peripheral lymphocyte balance typing, specific cytokines and interleukins profiling can be proposed as predictive biomarkers of implantation before embryo transfer.

Evidence for the effectiveness of immunologic therapies in women with subfertility and/or undergoing assisted reproduction

Implantation is a critical step in the establishment of a successful pregnancy, depending on a complex immune-endocrine dialogue between the developing embryo and maternal endometrium. Research suggests that altered immunity in the maternal decidua results in implantation impairment and failure. Immunomodulatory drugs have, thus, been widely used in assisted conception to aid embryo implantation, despite an absence of consensus on their effectiveness and safety. We conducted a systematic review and meta-analysis of interventional studies investigating the use of immunomodulators in women undergoing assisted reproduction. Evidence was uncertain of an effect for most of the included interventions, owing to heterogeneous findings and a paucity of high-quality studies. For certain patient subgroups, however, the use of specific immunomodulatory therapies may offer some benefit. There is a need for further large randomized controlled trials to corroborate these findings.

Clinical outcome of intrauterine administration of peripheral mononuclear cells or human chorionic gonadotropin in unexplained implantation failure

PROBLEM

Intrauterine administration of autologous peripheral blood mononuclear cells (PBMCs) or human chorionic gonadotropin (hCG) has been proposed to facilitate embryo implantation, while its effect on clinical outcome of women with previous implantation failure (RIF) in frozen/thawed embryo transfer (FET) cycles is still unclear.

METHOD OF STUDY

A total 523 patients having not experienced successful clinical pregnancy were enrolled in our study, including 207 repeat implantation failure (RIF) patients, and 316 patients with previous implantation failures but failed to meet the diagnostic criteria for RIF (non-RIF). Autologous PBMCs were cultured with hCG for 4 h in the hCG-activated PBMC-treated group (n = 73 in RIF patients, n = 112 in non-RIF patients), and then intrauterine administered 2 days before FET. In the hCG-treated group (n = 67 in RIF patients, n = 100 in non-RIF patients), recombinant hCG was administered 2 days before FET. The control group (n = 67 in RIF patients, n = 104 in non-RIF patients) underwent FET without intrauterine administration.

RESULTS

In RIF patients, the clinical pregnancy rate of the above three groups are 56.16%, 53.73%, and 43.28%, respectively (p = .276). The implantation rate and live birth rate showed no significant differences (p > .05). For non-RIF patients, higher clinical pregnancy rate was also seen in PBMC intrauterine group (57.15%) and hCG intrauterine group (58.00%) than controls (50.96%) but without statistical significance. There were no significant differences of implantation rate and live birth rate (p > .05).

CONCLUSION

Intrauterine administration of hCG-activated PBMC and hCG did not improve clinical outcomes for both RIF and non-RIF patients before FET embryo transfer.

Effect of human peripheral blood mononuclear cells (hPBMCs) on mouse endometrial cell proliferation: a potential therapeutics for endometrial regeneration

OBJECTIVES

The persistently thin endometrium is a major cause of repeated implantation failure; however, there is no definite treatment for it yet. This study aimed to confirm the potential of human peripheral blood mononuclear cells (hPBMCs) as a therapeutic agent for endometrial regeneration.

DESIGN

Experimental study Participants/Materials, Setting, Methods: To assess the in vitro effect of hPBMC, the human primary endometrial epithelial cell lines SNU-685 and SNU-1077 were co cultured with or without 1×10^5 hPBMCs for 24 hours. To evaluate the in vivo effect, either 1×10^5 hPBMCs in PBS or PBS alone were injected into the left uterine horn of NOD-SCID mice, and the right untreated uterine horn was used as control.

RESULTS

Co-culture with hPBMCs stimulated significant proliferation in both SNU-685 and SNU-1077 cell lines (p=0.002 and 0.044, respectively). Moreover, treatment with hPBMCs significantly increased the thickness in all parts of the endometrium compared with that in the untreated control uterine horn (proximal: 1.69±0.19 vs. 1.00±0.10, p=0.009; middle: 1.51±0.14 vs. 1.00±0.12, p=0.010; distal: 1.72±0.22 vs. 1.00±0.12, p=0.003, respectively). Compared with the PBS injection group, the hPBMC injection group had significantly thickened endometrium in the middle (P=0.036) and distal segments (P=0.002) of the uterine horn. Immunohistochemical analysis revealed the presence of exogenously injected hPBMCs in the uterus of recipient mice. hPBMC-recipient mice had cyclic uterus with normal histology in the endometrium.

LIMITATIONS

hPBMCs were not applied directly to a mouse model with thin endometrium, so further study is needed.

CONCLUSION

The beneficial effect of hPBMCs on endometrium may suggest their clinical feasibility for the safe treatment of infertile patients with persistently thin endometrium.

Intrauterine interventions for women with two or more implantation failures: A systematic review and network meta-analysis

OBJECTIVE

To compare the effectiveness of different intrauterine interventions for women with two or more unexplained implantation failures.

DESIGN

A systematic review and network meta-analysis of randomized controlled trials (RCTs).

PATIENTS

Women with two or more implantation failures undergoing fresh or frozen embryo transfer (ET).

INTERVENTIONS

An electronic search of the following databases: Pubmed, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase.

MAIN OUTCOME MEASURES

Clinical pregnancy, live birth/ongoing pregnancy, and miscarriage.

RESULTS

We included 21 RCTs(3079 women) in the network meta-analysis. The network meta-analysis showed that compared with control treatment, platelet-rich plasma(PRP), peripheral blood mononuclear cells (PBMC), granulocyte colony-stimulating factor(G-CSF), human chorionic gonadotropin(HCG), and endometrial scratch(ES) significantly increased clinical pregnancy(OR 3.78, 95% CI 2.72 to 5.25; 2.79, 95% CI 1.75 to 4.45; 1.93, 95% CI 1.37 to 2.72; 1.80, 95% CI 1.18 to 2.72; 1.75, 95% CI 1.29 to 2.36, respectively). PRP ranked the highest in improving clinical pregnancy, followed by PBMC, G-CSF, HCG, and ES. Compared with control treatment, PRP, PBMC, and ES significantly increased live birth/ongoing pregnancy (OR 5.96, 95% CI 3.38 to 10.52; OR 2.55, 95% CI 1.27 to 5.11; OR 1.70, 95% CI 1.07 to 2.69, respectively). PRP ranked the highest in improving live birth/ongoing pregnancy, followed by PBMC, and ES.

CONCLUSIONS

PRP is the most effective intrauterine intervention in improving pregnancy outcome in women with two or more implantation failures.

Intrauterine administration of peripheral blood mononuclear cells (PBMCs) improves embryo implantation in mice by regulating local Treg/Th17 cell balance

Immune imbalance of Treg/Th17 cells may contribute to recurrent implantation failure (RIF) during in vitro fertilization and embryo transfer (IVF-ET). In this study, we sought to determine the effect of intrauterine administration of mouse PBMCs prior to embryo implantation on endometrial receptivity and embryo implantation, and examine the underlying mechanism of Treg/Th17 cell balance following intrauterine administration of PBMCs. Pregnant mice were randomly divided into three groups: control group, embryo implantation dysfunction (EID) group, and EID with PBMCs group, and the number of embryo implantation sites was recorded during early pregnancy (Pd7.5). The balance of Treg/Th17 cells in the peripheral blood, spleen, and local implantation sites was detected during the peri-implantation period (Pd4.0) and early pregnancy (Pd7.5). The EID group demonstrated a significant decrease in the number of embryo implantation sites, while the EID with PBMCs group demonstrated higher number of embryo implantation sites compared to the EID group. The balance of Treg/Th17 cells in the peripheral blood and spleen tissues was not significantly different between the aforementioned groups. However, the local uterine ratio of the Treg/Th17 cells increased in the EID with PBMCs group compared to that in the EID group. Collectively, we found that intrauterine administration of PBMCs prior to embryo implantation effectively promotes embryo implantation rates. This may be attributed to the improvement in the local immune balance of Treg and Th17 cells compared with the overall immune balance.

Novel therapeutic options for treatment of recurrent implantation failure

Despite the challenges in studying recurrent implantation failure, progress is currently being made in therapeutic options to help those who suffer from recurrent implantation failure. Three of the most promising therapeutic options for recurrent implantation failure include immune therapies such as peripheral blood mononuclear cells, platelet rich plasma and subcutaneous granulocyte-colony stimulating factor.

Intrauterine administration of activated peripheral blood mononuclear cells in intrauterine insemination: a prospective double-blind randomized clinical trial

OBJECTIVE

To evaluate the effect of intrauterine administration of activated peripheral blood mononuclear cells (PBMC) on intrauterine insemination (IUI) success rates.

METHODS

This prospective double-blind randomized parallel clinical trial included 213 patients undergoing IUI at the Fertilys clinic. PBMC were isolated on the day of ovulation (day 0; D0) and stimulated with phytohemagglutinin (PHA) and human chorionic gonadotropin (hCG) for 48 hours (day 2; D2). Patients in the PBMC group (n = 108) underwent in utero administration of 1.10⁶ cells on D2, while patients in the control group (n = 105) were administered sperm-washing medium. Distribution of CD4 T lymphocyte populations (n = 61) was assessed on D0 and D2. Pregnancy and live birth rates were also evaluated.

RESULTS

Demographic and clinical characteristics, pregnancy rates, and live birth rates were not significantly different between the PBMC and control groups. Significantly higher levels of T helper (Th) 2, Th22, and T regulatory cells (P < 0.0001) and lower levels of Th17 cells were observed in hCG-activated PBMC at D2 than at D0.

CONCLUSION

Intrauterine administration of PBMC was not beneficial in IUI patients. New clinical approaches to better identify patients requiring endometrium immunomodulation needs to be addressed.

Effect of growth hormone on thin endometrium via intrauterine infusion

Background

A thin endometrium has become a common reason for the repeated implantation failure. Growth hormone (GH) can regulate the proliferation and metabolism of endometrial cells. The aim of this study was to explore the effect of GH on thin endometrium.

Methods

A total of 48 female Sprague-Dawley (SD) rats were randomly assigned to the following 4 groups with 12 rats in each group: blank control, model, subcutaneous, and GH groups. The blank control group was untreated and maintained in a routine manner. The model, subcutaneous, and GH groups were intrauterine perfused with 95% ethanol during estrus. After 6–8 h, the model group was intrauterine perfused with 0.2 mL normal saline, the subcutaneous group received subcutaneous injection of 0.12 mg/kg GH dissolved in 0.2 mL normal saline, and the GH group was intrauterine perfused with 0.12 mg/kg GH dissolved in 0.2 mL normal saline. Hematoxylin and eosin (HE) staining was used to examine the thickness of the endometrium. The expression of cytokeratin and vimentin was detected by western blotting and immunohistochemistry.

Results

The intima thickness in the GH group and blank control group was increased compared with that in the model group (P<0.01). The intima thickness in the subcutaneous group was increased compared with that in the model group, but there was no significant difference. The expression of vimentin and cytokeratin was increased in the GH (P<0.01) and blank control (P<0.01) groups compared with that in the model group.

Conclusions

Intrauterine perfusion of GH can promote the regeneration and repair of thin endometrium in rats. The therapeutic effect of uterine infusion of GH is better than that of subcutaneous injection of GH.

The Role of Stem Cells and Their Derived Extracellular Vesicles in Restoring Female and Male Fertility

Infertility is a globally recognized issue caused by different reproductive disorders. To date, various therapeutic approaches to restore fertility have been attempted including etiology-specific medication, hormonal therapies, surgical excisions, and assisted reproductive technologies. Although these approaches produce results, however, fertility restoration is not achieved in all cases. Advances in using stem cell (SC) therapy hold a great promise for treating infertile patients due to their abilities to self-renew, differentiate, and produce different paracrine factors to regenerate the damaged or injured cells and replenish the affected germ cells. Furthermore, SCs secrete extracellular vesicles (EVs) containing biologically active molecules including nucleic acids, lipids, and proteins. EVs are involved in various physiological and pathological processes and show promising non-cellular therapeutic uses to combat infertility. Several studies have indicated that SCs and/or their derived EVs transplantation plays a crucial role in the regeneration of different segments of the reproductive system, oocyte production, and initiation of sperm production. However, available evidence triggers the need to testify the efficacy of SC transplantation or EVs injection in resolving the infertility issues of the human population. In this review, we highlight the recent literature covering the issues of infertility in females and males, with a special focus on the possible treatments by stem cells or their derived EVs.

Intrauterine administration of peripheral blood mononuclear cells activated by human chorionic gonadotropin in patients with repeated implantation failure: A meta-analysis

The purpose of this study was to assess whether intrauterine administration of peripheral blood mononuclear cells (PBMCs) activated by human chorionic gonadotropin (hCG) could improve the pregnancy and live birth rates in women with repeated implantation failure (RIF), and whether the parameters of co-culture of hCG and PBMCs would affect the clinical outcomes. Six databases (PubMed, Ovid, Medline, NCBI, Cqvip and Wanfang) were searched up to October 2020 by two independent reviewers. Seven studies were included according to specific inclusion and exclusion criteria. A meta-analysis showed that the pregnancy and live birth rates were significantly increased in the case group compared with the control group (odds ratio [OR]: 3.43, 95 % confidence interval [CI]: 1.78-6.61; P =  0.0002 and OR: 2.79, 95 % CI: 1.09-7.15; P =  0.03), especially when hCG was cultured with PBMCs for 48 h or PBMCs administration was performed two or three days before embryo transfer (ET). Neither the dosage of the hCG co-cultured with PBMCs nor the mean concentration of the administered PBMCs appeared to influence the therapeutic efficiency. In conclusion, intrauterine administration of PBMCs co-cultured with hCG for 48 h, conducted two or three days before ET, could be an effective therapy for women experiencing RIF. Due to the limitations of sample size and quality of the included studies, further high-quality studies with large sample sizes are warranted to optimize the parameters of hCG and PBMC co-culture to help more RIF patients benefit from this therapy.

Approaches to Improve Endometrial Receptivity in Case of Repeated Implantation Failures

Repeated implantation failures are a constant challenge in reproductive medicine with a significant impact both on health providers and on infertile couples. Several approaches have been proposed so far as effective; however, accumulative data have clarified that most of the treatment options do not have the evidence base for a generalized application to be suggested by the relevant societies. Implantation failures are attributed to either poor quality embryos or to defected endometrial receptivity. The current review aims to summarize in a systematic way all the new trends in managing RIF via interference with endometrial receptivity. The authors focus mainly, but not exclusively, on endometrial injury prior to embryo transfer and endometrial priming with autologous cells or biological agents. To this direction, a systematic search of the Pubmed database has been conducted taking into account the emerged evidence of the last two decades. All the suggested interventions are herein presented and analyzed in terms of reproductive outcomes. It is evident that properly powered and designed randomized trials are needed to support a new standard approach in RIF treatment that will safely be incorporated in national and international guidelines.

Lymphocyte immunotherapy in recurrent miscarriage and recurrent implantation failure

PROBLEM

Lymphocyte immunotherapy (LIT) emerged in the early 1980s as a new therapeutic proposal for couples with a history of recurrent miscarriages (RM). However, in the early 2000s, the effectiveness of LIT was questioned. Recently, meta-analyses have observed the effectiveness and safety of LIT in treating couples with RM. Some studies evaluated the use of LIT in recurrent implantation failure (RIF) in in vitro fertilization cycles.

METHODS

This systematic and narrative review evaluated the data available in the literature regarding the efficacy and safety of the use of LIT. Searches in PubMed/Medline, Embase, and Cochrane Library databases were conducted, using the following keywords: "recurrent miscarriage," "lymphocyte immunotherapy," and "recurrent implantation failure".

RESULTS

This review describes the historical aspects of LIT and discusses its protocols, mechanisms of action, side effects, complications, and current evidence of the effectiveness in cases of reproductive failure. It also discusses the use of LIT during the COVID-19 pandemic and new immunological therapies.

CONCLUSION

In the vast majority of studies, the use of LIT for RM couples has shown an improvement in pregnancy outcomes. The most of the current studies that support the evidence are quasi-experimental, with few randomized, double-blind studies (Level of evidence III). However, the current evidence are not convincing for the use of LIT in RIF patients.

Will stem cells from fat and growth factors from blood bring new hope to female patients with reproductive disorders?

Female reproductive system disorders (FRSD) with or without infertility are prevalent women's health problems with a variety of treatment approaches including surgery and hormone therapy. It currently considering to sub-branch of regenerative medicine including stem cells or growth factors injection-based delivery treatment might be improved female reproductive health life. The most common products used for these patients treatment are autologous cell or platelet-based products from patients, including platelet-rich plasma, plasma rich in growth factor, platelet-rich fibrin, and stromal vascular fraction. In this review, we discuss each of the above products used in treatment of FRSD and critically evaluate the clinical outcome.

Role of intrauterine administration of transfected peripheral blood mononuclear cells by GM-CSF on embryo implantation and pregnancy rate in mice

One of the effective treatments in women with recurrent implantation failure (RIF) is the use of immune cells to facilitate embryo implantation. Previous studies have shown that intrauterine transmission of peripheral blood mononuclear cells (PBMC) increased the embryo implantation rate. In this study using B6D2F1 (C57BL/6 × DBA2) mice, a fragment of the granulocyte macrophage colony-stimulating factor (Gm-csf) gene was cloned into an enhanced green fluorescent protein vector (pEGFP-N1) and then transfected into PBMC. The protein level of GM-CSF was evaluated in the transfected PBMC and untransfected PBMC by ELISA. Attachment of mouse embryos and the mRNA expression levels of leukemia inhibitory factor (Lif), vascular endothelial growth factor (Vegf), matrix metalloproteinase 9 (Mmp9), Gmcsf-receptor (Gmcsf-r) and interleukin 6 (Il6) in vitro were assessed by real-time PCR in endometrial cells. To determine the pregnancy rate and number of implantation sites in vivo, the mouse uterine horns were analyzed on Day 7.5 post coitum. A greater amount of GM-CSF was produced in PBMC transfected with recombinant vector (552 pg/mL) compared with the untransfected PBMC (57 pg/mL) and PBMC transfected with empty vector (34 pg/mL) (P < 0.05). The data showed that the embryo attachment rate and mRNA expression levels (Vegf [1.7-fold], Mmp9 [1.4-fold], Lif [1.5-fold], Gm-csf r [1.6-fold] and Il6 [1.2-fold]) in the in vitro study (P < 0.01), pregnancy rate (P < 0.01) and number of implantation sites (P < 0.01) in the in vivo investigation (P < 0.05) were increased in PBMC transfected with recombinant vector compared with the PBMC group. The study demonstrated that, in mice, endometrium immunotherapy with transfected PBMC that contained recombinant GM-CSF before embryo implantation was effective in improving embryo implantation and endometrial receptivity.

Efficacy of therapies and interventions for repeated embryo implantation failure: a systematic review and meta-analysis

The aim of the present systematic review and meta-analysis was to assess the effect of the different therapeutic options for repeated embryo implantation failure (RIF) on a subsequent IVF cycle outcome. Twenty-two RCTs and nineteen observational studies were included. Pooling of results showed a beneficial effect of intrauterine PBMC infusion on both CPR (RR 2.18; 95% CI 1.58-3.00; p < 0.00001; OR 2.03; 95% CI 1.22-3.36; p = 0.006) and LBR (RR 2.41; 95% CI 1.40-4.16; p = 0.002; OR 3.73; 95% CI 1.13-12.29; p = 0.03), of subcutaneous G-CSF administration on CPR (RR 2.29; 95% CI 1.58-3.31; p < 0.0001) and of intrauterine PRP infusion on CPR (RR 2.45; 95% CI 1.55-3.86; p = 0.0001). Observational studies also demonstrated a positive effect of IVIG and intrauterine hCG infusion on both CPR and LBR and of atosiban on CPR. Studies investigating intrauterine G-CSF infusion, LMWH, intravenous intralipid, hysteroscopy, blastocyst-stage ET, ZIFT, PGT-A and AH failed to observe an impact on IVF outcome. The quality of the evidence that emerged from RCTs focused on intrauterine PBMC infusion and subcutaneous G-CSF administration was moderate. For all other therapies/interventions it varied from low to very low. In conclusion, intrauterine PBMC infusion and subcutaneous G-CSF administration are the most promising therapeutic options for RIF. However, further well conducted RCTs are necessary before their introduction into clinical practice.

Efficacy of intrauterine perfusion of peripheral blood mononuclear cells (PBMC) for infertile women before embryo transfer: meta-analysis

This meta-analysis was intended to evaluate the effects of intrauterine perfusion of peripheral blood mononuclear cells (PBMC) on the pregnancy outcomes including clinical pregnancy rates, embryo implantation rates, live birth rates and miscarriage rates of infertile women who were undergoing in vitro fertilisation (IVF) treatment. By searching Pubmed, Embase database, five articles meeting the inclusion criteria were included, and 1173 women were enrolled (intrauterine PBMC group: n = 514; NO-PBMC group: n = 659). For the entire IVF/ICSI population and one or two embryo transfer failure patients, there was no significant difference in endometrial thickness, embryo implantation rates, live birth rates, and miscarriage rates between the PBMC group and NO-PBMC group. Although the clinical pregnancy rates of the PBMC group were higher than that of the NO-PBMC group, the confidence interval was close to the line of unity. As for the patients with three or more implantation failures, the clinical pregnancy rates, embryo implantation rates and live birth rates were much higher in the PBMC group than that of the NO-PBMC group. In summary, current evidence suggests that intrauterine perfusion of PBMC can significantly improve pregnancy outcomes in patients who have three or more implantation failures.Impact statementWhat is already known on this subject? An increasing number of studies have shown that immune cells play an important role in embryo transfer. There is no reliable evidence to confirm the clinical efficacy of intrauterine perfusion of PBMC.What do the results of this study add? The current evidence suggests that intrauterine perfusion of PBMC can significantly improve pregnancy outcomes in patients who have three or more implantation failures.What are the implications of these findings for clinical practice and/or further research? To the best of our knowledge, this meta-analysis is the first to evaluate the effect of intrauterine perfusion of PBMC on pregnancy outcomes before embryo transfer. Our study indicated that intrauterine perfusion of PBMC significantly increased clinical pregnancy rates, embryo implantation rates, and live birth rates in patients who failed more than three implants.

Intrauterine administration of autologous hCG- activated peripheral blood mononuclear cells improves pregnancy outcomes in patients with recurrent implantation failure; A double-blind, randomized control trial study

We aimed to investigate the effect of intrauterine administration of autologous hCG-activated PBMCs in RIF women with low Th-17/Treg cell ratio. 248 women with a history of implantation failure volunteered to receive PBMC-therapy. After immunologic consultation and doing flow cytometry analysis, 100 women with at least three IVF/ET failure who had low Th-17/Treg ratio in comparison with healthy control were enrolled in this study. These 100 patients were randomly divided into two groups as PBMC receiving (n = 50) and controls (n = 50). Then PBMCs were obtained from patients and treated with hCG for 48 h. Afterward, PBMCs were administered into the uterine cavity of the patient in the study group, two days before ET. The concentration of inflammatory cytokines was examined in the supernatant of cultured PBMCs after 2, 24, and 48 h of incubation using the ELISA method. The frequency of Th-17, Treg, and the Th-17/Treg ratio was significantly lower in RIF women than the healthy controls (P < 0.0001). The secretion of inflammatory cytokines was significantly higher after 48 h compared to 2 and 24 h (P < 0.0001). The pregnancy and live birth rate were significantly increased in women undergoing the PBMC-therapy compared to control (PBS-injecting) group (P = 0.032 and P = 0.047, respectively). The miscarriage rate was considerably lower in PBMC-therapy group (P = 0.029). Our findings suggest that intrauterine administration of autologous in vitro hCG-activated PBMCs improves pregnancy outcomes in patients with at least three IVF/ET failures.

Intrauterine perfusion immunotherapies in recurrent implantation failures: Systematic review

Studies have investigated the gestational outcomes of new immunological therapies in the treatment of patients with recurrent implantation failure (RIF) in assisted reproductive technology (ART). The objective of this article is to assess the current state of evidence available in the literature on intrauterine perfusion immunotherapies in women undergoing ART treatments. By considering the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA), the authors performed systematic review by searching the databases of PubMed/MEDLINE and Scopus using the following key words: "recurrent implantation failure," "intrauterine infusion," "Platelet-Rich Plasma (PRP)," "Peripheral Blood Mononuclear Cells (PBMC)," "Granulocyte Colony-Stimulating Factor (G-CSF)," and "Human Chorionic Gonadotropin (hCG)." The authors analyzed the indications and the impact of new immunological therapies with intrauterine infusions on the pregnancy outcomes of patients undergoing ART. PRP, PBMC, G-CSF, and hCG were the four most used immunological therapies with intrauterine infusion. These new therapies appear to improve the results of ART treatments in cases of RIF. However, the small number of studies does not allow definitive conclusions about the effectiveness of these therapies.

Transcriptomic changes and potential regulatory mechanism of intrauterine human chorionic gonadotropin co-cultured with peripheral blood mononuclear cells infusion in mice with embryonic implantation dysfunction

Background

This study aimed to explore whether intrauterine infusion of peripheral blood mononuclear cells (PBMCs) could induce favorable transcriptomic changes in the endometrium for embryo implantation and the potential mechanism.

Methods

Twenty-one mice were randomly divided to five groups, including a normal pregnancy (NP) group, an embryo implantation dysfunction (EID) group, an EID with human chorionic gonadotropin (hCG) group, an EID with PBMCs group, and an EID with hCG co-cultured with PBMCs group. The endometrium in the implantation window from mice were collected and determined by RNA sequencing (RNA-Seq), and the expression of significantly different genes with high degree of coincidence was recommended and validated by quantitative real-time polymerase chain reaction (qRT-PCR).

Results

There were totally 1,366 up-regulated and 1,374 down-regulated genes in the EID mice compared with the normal pregnant mice. We selected (fold change ≥2, P<0.05) and verified the candidate genes associated with embryo implantation, immune response and other reproductive processes in previous reports by qRT-PCR. Leukemia inhibitory factor (LIF), solute carrier family 15 member 2 (SLC15A2), retinoic acid receptor responder 1 (RARRES1), vascular cell adhesion molecule 1 (VCAM1) were down-regulated and musculin (MSC), chemokine (C-X-C motif) ligand 14 (CXCL14) were up-regulated significantly in EID group (P<0.05), and the synergistic effects of hCG were seen. In addition, the expression of glucocorticoid receptor (GR)-β in PBMCs of NP mice was higher than that of EID mice, and up-regulated GR-β in EID mice could significantly increase the expression of LIF, SLC15A2, RARRES1 and VCAM1, and decrease the expression of CXCL14 and MSC, which indicated GR-β might be a transcriptional factor of the six genes above.

Conclusions

Intrauterine PBMCs perfusion might improve the performance of impaired endometrial receptivity by regulating LIF, SLC15A2, RARRES1, VCAM1, MSC as well as CXCL14, and hCG could enhance the effect of PBMCs. In addition, GR-β, as a transcriptional factor, could regulate the six genes in PBMCs.

Promoting Roles of Embryonic Signals in Embryo Implantation and Placentation in Cooperation with Endocrine and Immune Systems

Embryo implantation in the uterus is an essential process for successful pregnancy in mammals. In general, the endocrine system induces sufficient embryo receptivity in the endometrium, where adhesion-promoting molecules increase and adhesion-inhibitory molecules decrease. Although the precise mechanisms remain unknown, it is widely accepted that maternal–embryo communications, including embryonic signals, improve the receptive ability of the sex steroid hormone-primed endometrium. The embryo may utilize repulsive forces produced by an Eph–ephrin system for its timely attachment to and subsequent invasion through the endometrial epithelial layer. Importantly, the embryonic signals are considered to act on maternal immune cells to induce immune tolerance. They also elicit local inflammation that promotes endometrial differentiation and maternal tissue remodeling during embryo implantation and placentation. Additional clarification of the immune control mechanisms by embryonic signals, such as human chorionic gonadotropin, pre-implantation factor, zona pellucida degradation products, and laeverin, will aid in the further development of immunotherapy to minimize implantation failure in the future.

Human Chorionic Gonadotropin-Mediated Immune Responses That Facilitate Embryo Implantation and Placentation

Human chorionic gonadotropin (hCG) serves as one of the first signals provided by the embryo to the mother. Exactly at the time when the first step of the implantation process is initiated and the blastocyst adheres to the maternal endometrium, the embryonic tissue starts to actively secrete hCG. Shortly thereafter, the hormone can be detected in the maternal circulation where its concentration steadily increases throughout early pregnancy as it is continuously released by the forming placenta. Accumulating evidence underlines the critical function of hCG for embryo implantation and placentation. hCG not only regulates biological aspects of these early pregnancy events but also supports maternal immune cells in their function as helpers in the establishment of an adequate embryo-endometrial relationship. In view of its early presence in the maternal circulation, hCG has the potential to influence both local uterine immune cell populations as well as peripheral ones. The current review aims to summarize recent literature on the participation of innate and adaptive immune cells in embryo implantation and placentation with a specific focus on their regulation by hCG.

BEEF SPECIES-RUMINANT NUTRITION CACTUS BEEF SYMPOSIUM: Maternal immune modulation prior to embryo arrival in the uterus is important for establishment of pregnancy in cattle1

In 1953, Sir Peter Medawar first recognized the allogeneic properties of a developing conceptus and rationalized that an "immune-tolerant" physiological state must exist during pregnancy. Early theories speculated that the conceptus evaded the maternal immune system completely, but 40 yr after Medawar's observations, Wegmann proposed that the maternal immune system shifts the cytokine profile away from inflammatory cytokine production when an embryo is present. The economic consequences and production losses of subfertile animals have been well documented in studies evaluating calving distribution. Despite advances in understanding infertility or subfertility, few technologies exist to identify subfertile animals or improve fertility beyond hormonal intervention associated with synchronization protocols. Work in rodents and some livestock species indicates that the uterine immune cell population shifts dramatically after copulation and these early immune-modulated events establish a receptive uterine environment. Clearly, as evident in embryo transfer, the presence of a conceptus is sufficient to establish communication for pregnancy establishment but does not rule out the importance of other physiological events to prime the maternal immune system prior to blastocyst arrival in the uterus. In support of this concept, work in our laboratory and by others has demonstrated that autologous intrauterine transfer of peripheral immune cells prior to embryo transfer can increase pregnancy rates and accelerate conceptus development in women and cattle. Understanding aberrant immune regulation in subfertile animals may provide markers for subfertility or targets for clinical intervention to enhance fertility, particularly when using reproductive technologies.

Endometrium immunomodulation by intrauterine insemination administration of treated peripheral blood mononuclear cell prior frozen/thawed embryos in patients with repeated implantation failure

In assisted reproductive technology (ART) programmes, approximately 10% of infertile patients have at least two or three repeated implantation failures (RIFs) after an in vitro fertilization (IVF) protocol. Successful implantation mainly depends on local immune tolerance mechanisms involving a spectrum of cytokines, interleukins and growth factors. The latter have played pivotal roles in the recruitment of immune cells (and notably T-lymphocyte cells). In total, 250 couples participating in frozen-thawed embryo transfer programme were incorporated in a randomized clinical trial (peripheral blood mononuclear cells (PBMC) subgroup: n=122; control subgroup: n=128). In the PBMC group, a blood sample was collected 5 days before the scheduled frozen-thawed embryo transfer; PBMCs were isolated using Ficoll separation and then cultured for 72 h. Two days prior to embryo transfer, 0.4 ml of cultured PBMCs were transferred into the patient's uterus. Although the clinical pregnancy rate was higher in the PBMC group (34.4%) than in the control group (23.4%), this difference was not statistically significant (P=0.05 in a chi-squared test). Nevertheless, when we limited the analysis to patients with ≥3 RIFs (n=138), there was a significant difference in the clinical pregnancy rate between the PBMC group (38.6%) and the control group (19.7%; P=0.01). Our results imply that PBMC transfer can be part of effective fertility treatment for patients with RIF.

Intrauterine CRH-treated PBMC in repeated implantation failure

BACKGROUND

The intrauterine administration of activated autologous peripheral blood monocytes (PBMC) prior to embryo transfer seems to improve reproductive outcomes in women with repeated implantation failure (RIF). We have previously shown that the intrauterine administration of PBMC treated with corticotropin-releasing hormone (CRH) prior to blastocyst transfer (day 5) improves significantly the clinical pregnancy rate of women with RIF. In the present crossover pilot study, we have investigated whether CRH-PBMC treatment could be of benefit in case of fresh early cleavage stage embryo transfer (day 3) in women with RIF.

METHODS

Twenty-six (n = 26) women with at least three previous failed IVF attempts and no history of clinical pregnancy in the past were recruited in this study. Ovarian stimulation was performed following either the long or the short protocol. PBMC were collected during the oocyte retrieval, were treated with CRH, and transferred in the uterine cavity 2 days later. Good quality cleavage stage embryos were transferred at day 3, following oocyte retrieval.

RESULTS

Following the intrauterine administration of CRH-treated autologous PBMC, 15/26 clinical pregnancies occurred (57.69%). Compared to the null result of the same women prior to recruitment, this observation was considered significant (P < 10^-2 ).

CONCLUSION

Our findings further support the role of the intrauterine administration of CRH-treated PBMC as an effective approach when transferring cleavage stage embryos in women with RIF. Prospective randomized studies are needed to clarify whether such intervention could be of benefit in clinical practice.

Platelet-rich plasma or blood-derived products to improve endometrial receptivity?

The use of platelet-rich plasma (PRP) to improve endometrial receptivity is gaining increasing attention in assisted reproduction technologies. The authors report that autologous PRP intrauterine administration improves pregnancy and birth rates, particularly in cases of patients presenting poor endometrial growth. Different groups of scientists proposed a similar approach years ago using whole blood-derived products also to improve endometrial receptivity. The important role played by cytokines and growth factors during embryo implantation has been well-known for a long time. These signaling molecules are present and released by blood cells during physiological, normal endometrial growth and implantation. Similar blood mediators are released from platelet granules upon a blood vessel injury. Methods described for PRP preparation for intrauterine administration are not precise, and they seem to be similar to those used to prepare peripheral blood-derived products. Thus, it is possible that when preparing PRP from whole blood, the final plasma product used as "PRP" contains platelets in addition to the important cytokines and growth factors released by the peripheral blood mononuclear cells present in the whole blood. Precise knowledge of the identity, concentration, and effects of the individual blood factors, their origin, whether platelets or blood mononuclear cells, will greatly contribute to improve and to make results obtained in fertility treatments more repeatable.

The role of immunotherapy in in vitro fertilization and recurrent pregnancy loss: a systematic review and meta-analysis

OBJECTIVE

To study the current evidence on the role of immunotherapy in IVF and in the management of recurrent pregnancy loss (RPL).

DESIGN

Systematic review and meta-analysis.

SETTING

A literature search was performed using MEDLINE, PUBMED, CINAHL, and EMBASE until May 2017. Only randomized controlled trials were included, and a meta-analysis was carried out where appropriate.

PATIENT(S)

Women undergoing IVF treatment with or without a history of recurrent implantation failure and women with idiopathic RPL.

INTERVENTION(S)

Assessment of the efficacy of commonly used immunomodulators such as IV use of [1] immunoglobulin, [2] lymphocyte immunotherapy and [3] intralipid; intrauterine infusion of [4] granulocyte colony-stimulating factor and [5] peripheral blood mononuclear cells; subcutaneous administration of [6] TNF-alpha inhibitors, [7] leukaemia inhibitory factor; and oral administration of [8] glucocorticoids.

MAIN OUTCOME MEASURE(S)

The primary outcomes were live birth rate and miscarriage rate; secondary outcome was clinical pregnancy rate.

RESULT(S)

Of the 7,226 publications identified, 53 were selected during the initial screening; 30 satisfied the selection criteria and were included in this review.

CONCLUSION(S)

The available medical literature shows controversial results about the role of immunotherapy when used for improving reproductive outcomes. This study did not show a role for immunotherapy in improving the live birth rate in women undergoing IVF treatment or in the prevention of idiopathic RPL. Currently, immunotherapy should be used in the context of research and should not be used in routine clinical practice to improve reproductive outcomes.

Intrauterine administration of peripheral mononuclear cells in recurrent implantation failure: a systematic review and meta-analysis

It has been proposed that intrauterine administration of peripheral blood mononuclear cells (PBMCs) modulates maternal immune response through a cascade of cytokines, chemokines and growth factors to favor implantation. We conducted a meta-analysis to verify the effect of intrauterine PBMC administration on the outcome of embryo transfer in women with recurrent implantation failure (RIF). All relevant trials published in PubMed, Web of Science and Cochrane library databases were searched. Two randomized controlled trials and three cohort studies (1173 patients in total) matched the inclusion criteria. No differences in live birth rates were seen between the PBMC-treated patients and controls (OR: 1.65, 95% CI: 0.84–3.25; p = 0.14; I²: 66.3%). The clinical pregnancy rate was significantly higher in women who received intrauterine PBMCs before embryo transfer compared with those who did not (OR: 1.65, 95% CI: 1.30–2.10; p = 0.001, heterogeneity; I²: 60.6%). Subgroup analyses revealed a significant increase in clinical pregnancy rates with the administration of PBMCs in women with ≥3 previous failures compared with controls (OR: 2.69, 95% CI: 1.53–4.72; p = 0.001, I²: 38.3%). In summary, the data did not demonstrate an association between the administration of PBMCs into the uterine cavity before fresh or frozen-thawed embryo transfer and live birth rates in women with RIF. Whether intrauterine PBMC administration significantly changes live birth and miscarriage rates requires further investigation.

Effect of hysteroscopy before starting in-vitro fertilization for women with recurrent implantation failure: A meta-analysis and systematic review

OBJECTIVE

To study if hysteroscopy (HSC) before starting an in-vitro fertilization (IVF) cycle improves IVF outcomes in women with recurrent implantation failure (RIF).

METHODS

The Medline, Cochrane, EMBASE, and Google Scholar databases were searched using the following keywords until March 31, 2017: in-vitro fertilization; infertility; hysteroscopy; recurrence; embryo implantation; and pregnancy. Randomized controlled trials (RCTs), two-arm prospective studies, and retrospective studies were included.

RESULTS

Three RCTs, 3 nonrandomized prospective studies, and 2 retrospective cohort studies were included. The eligible studies included 3932 women with RIF: 1841 in the HSC group and 2091 in the control group. The clinical pregnancy rate and implantation rate was significantly higher in the HSC group compared with the control group (for clinical pregnancy rate, pooled odds ratio [OR] = 1.64, 95% confidence intervals [CI]: 1.30-2.07, P < 0.001; for implantation rate, pooled OR = 1.22, 95% CI: 1.02-1.45, P = 0.025). The live birth rate (pooled OR = 1.30, 95% CI: 0.90-1.88, P = 0.168) and the miscarriage rate (pooled OR = 0.94, 95% CI: 0.66-1.35, P = 0.744) of the 2 groups were not statistically significantly.

CONCLUSIONS

HSC improved the implantation rate and clinical pregnancy rates, but failed to improve live birth rate and did not affect the miscarriage rate in women with RIF undergoing IVF. Since HSC plays a significant role in pregnancy and birth outcomes of women with RIF, further studies are warranted.

Intrauterine administration of human chorionic gonadotropin improves the live birth rates of patients with repeated implantation failure in frozen-thawed blastocyst transfer cycles by increasing the percentage of peripheral regulatory T cells

INTRODUCTION

Repeated implantation failure (RIF) frustrates both patients and their clinicians. Our aim was to observe the effects of intrauterine administration of human chorionic gonadotropin (hCG) on pregnancy outcomes of patients who received frozen-thawed embryo transfer (FET).

METHODS

A prospective cohort study was conducted to evaluate the impact of intrauterine administration of hCG on pregnancy outcomes in FET cycles of patients with RIF from January 1st 2016 to December 31st 2016. The treatment group (n = 153, 152 cycles) received an infusion of 500 IU of hCG diluted in normal saline 3 days before embryo transfer. The control group (n = 152, 151 cycles) received embryo transfer with a previous intrauterine injection of normal saline without hCG. Early morning fasting blood samples were obtained from each patient for the measurement of peripheral regulatory T cells (Tregs) on the day of embryo transfer. The outcome parameters including Tregs in each group were compared.

RESULTS

The patients in the hCG-treated group had significantly higher clinical pregnancy rates, implantation rates and live birth rates than the controls (37.5% versus 25.17%, 29.19% versus 19.4%, 26.97% versus 17.22%, respectively). They also had significantly higher percentages of peripheral Tregs than the controls (6.1 ± 0.6% versus 5.4 ± 1.0%). In addition, the clinical pregnancy rate, implantation rate and live birth rate in patients who received blastocyst transfer were significantly higher in the hCG-treated group when compared to the control group (41.38% versus 26.44%, 42.22% versus 26.14%, 33.33% versus 17.24%, respectively). We also showed that the clinical pregnancy rate, implantation rate and live birth rate were significantly higher in hCG-treated group when compared to the control group (49.12% versus 28.07%, 49.15% versus 28.07%, 40.35% versus 17.54%, respectively) of RIF patients with blastocyst transfer under 35 years, while there was on difference in patients above 35 years.

CONCLUSIONS

Intrauterine administration of hCG significantly improves the clinical pregnancy rate, implantation rate and live birth rate in FET cycles of patients with RIF by increasing Tregs. The treatment improves the pregnancy outcomes much more for younger RIF patients transferred blastocysts.

Inverted pyramid of prenatal care - is it enough? Should it be - extended inverted pyramid of prenatal care?

In recent years, the idea of the inverted pyramid of prenatal care and monitoring has emerged, for the purpose of prediction and prevention, early detection and treatment of health disorders of the fetus. Is this enough? If we analyze the period behind us, progress has been made in the field of detection of multiple pregnancies, dating of pregnancy and prenatal detection of chromosomal and structural fetal disorders, as well as a small amount of progress in terms of prediction and prevention of preeclampsia. If these disorders are the consequence of the disturbed or dysfunctional placentation, they are rooted at the time of implantation. This means that the changes that lead to the dysfunctional implantation should be sought in the pre-implantation period, in relation between the embryo and the endometrium. An extended inverted pyramid is necessary to find better results in perinatal medicine. This means that the interventions should be focused on the preconception and peri-implantation periods. The therapy should be on the subcellular and genetic level by applying the latest biotechnological procedures. It is possible that the time is approaching when the listed disorders of a pregnancy will be the indications for the application of a non stimulated in-vitro fertilization (IVF) (without ovary stimulating medication) with the use of new biotechnological achievements.

Endometrial CRH and implantation: from bench to bedside

Endometrial corticotropin-releasing hormone (CRH) has been described as a mediator of decidualisation and as a contributor of maternal-fetal immunotolerance. Deregulation of the CRH expression pattern has been associated with unfavourable reproductive outcomes as well as chronic endometrium-derived inflammatory disorders, such as endometriosis and adenomyosis. The current review summarises the evidence produced regarding the role of CRH in endometrial physiology and pathophysiology and highlights recent clinical data regarding the role of CRH in improving clinical pregnancy rates in women with repeated implantation failures following in vitro fertilisation and embryo transfer.

Progesterone-associated arginine decline at luteal phase of menstrual cycle and associations with related amino acids and nuclear factor kB activation

Background/Objectives

Given their role in female reproduction, the effects of progesterone on arginine and related amino acids, polyamines and NF-κB p65 activation were studied across the menstrual cycle.

Methods

Arginine, ornithine and citrulline as well as putrescine, spermidine, spermine, and N-acetyl-putrescine were determined in plasma, NF-κB p65 activation in peripheral blood mononuclear cells and progesterone in serum of 28 women at early (T1) and late follicular (T2) and mid (T3) and late (T4) luteal phase.

Results

Arginine and related amino acids declined from T1 and T2 to T3 and T4, while progesterone increased. At T3, arginine, ornithine, and citrulline were inversely related with progesterone. Changes (ΔT3-T2) in arginine, ornithine, and citrulline were inversely related with changes (ΔT3-T2) in progesterone. Ornithine and citrulline were positively related with arginine, as were changes (ΔT3-T2) in ornithine and citrulline with changes (ΔT3-T2) in arginine. At T2, NF-κB p65 activation was positively related with arginine. Polyamines did not change and were not related to progesterone. All results described were significant at P < 0.001.

Conclusions

This study for the first time provides data, at the plasma and PBMC level, supporting a proposed regulatory node of arginine and related amino acids, progesterone and NF-κB p65 at luteal phase of the menstrual cycle, aimed at successful preparation of pregnancy.

Clinical efficacy and mechanism of growth hormone action in patients experiencing repeat implantation failure

The objectives of this study were to investigate the clinical efficacy of growth hormone (GH) in patients experiencing repeat implantation failure (RIF) and explore the possible mechanism. Forty-two RIF patients undergoing in vitro fertilization - embryo transfer (IVF-ET) were enrolled in the present trial: 22 patients who received GH (treatment group) and 20 who did not receive GH (controls). The clinical pregnancy and live birth rates in the treatment group were significantly higher than those in the control group (both P < 0.05). The treatment group expressed significantly higher levels of growth hormone receptor (GHR) mRNA than the control group (P < 0.05). Further analysis showed that GH levels in follicular fluid were positively correlated with the expression levels of mRNA encoding GHR in granulosa cells (r = 0.460, P < 0.05). GH treatment enhanced IVF pregnancy outcomes and increased the expression of GHR in granulosa cells in fluid. GH levels in follicular fluid were positively correlated with the expression levels of GHR.

Intrauterine administration of autologous peripheral blood mononuclear cells (PBMCs) activated by HCG improves the implantation and pregnancy rates in patients with repeated implantation failure: a prospective randomized study

PROBLEM

Intrauterine administration of autologous peripheral blood mononuclear cells (PBMCs) activated by HCG in vitro was reported to improve implantation rates in patients with repeated failure of IVF-ET (in vitro fertilization-embryo transfer). In this article, the value of intrauterine administration of PBMCs before embryo transfer and its optimal cell culture method will be investigated.

METHOD OF STUDY

Patients who had not experienced successful pregnancy despite three or more IVF-ET sessions were enrolled in this study (n=240, 240 cycles). PBMCs were obtained from patients themselves and were cultured with HCG for 24 hours. Twenty-four hours later, PBMCs were then administered to the intrauterine cavity of that patient from the study group (n=93, 93 cycles). The control group (n=105, 105 cycles) underwent ET without intrauterine administration.

RESULTS

Clinical pregnancy rate, implantation rate, and miscarriage rate in the PBMC-treated group (46.24% and 23.66%, n=43 and 22, respectively) were significantly higher than those in the non-treated group (20.95% and 11.43%, P<.05; n=22 and 12, respectively).

CONCLUSION

These findings indicate that intrauterine administration of autologous PBMC activated by HCG in vitro effectively improves embryo implantation in patients with three or more IVF failures.

The Role of HCG in Implantation: A Mini-Review of Molecular and Clinical Evidence

Embryo implantation is a complex process involving continuous molecular cross-talk between the embryo and the decidua. One of the key molecules during this process is human chorionic gonadotropin (HCG). HCG effectively modulates several metabolic pathways within the decidua contributing to endometrial receptivity. Herein, a brief overview of the molecular mechanisms regulated by HCG is presented. Furthermore, we summarize the existing evidence regarding the clinical impact on reproductive outcomes after endometrial priming with HCG prior to embryo transfer. Although promising, further evidence is needed to clarify the protocol that would lead to beneficial outcomes.